(a) Field of the Invention
The present invention relates to a method and an apparatus for controlling priority in device-to-device communications.
(b) Description of the Related Art
With recent development of wireless communication systems, device-to-device (D2D) communications have become an issue. Particularly, as LTE-Advanced technology is commercially available, many D2D communications methods based on the LTE-Advanced technology have been researched.
According to the D2D communications, terminals form and maintain D2D communication networks by using radio resources that are dispersedly limited, in order to perform operations such as synchronization, peer discovery, paging, and data traffic communications.
In the synchronization operation, basic time and frequency synchronizations are performed between terminals through, e.g., a global positioning system (GPS). The peer discovery operation identifies neighboring terminals that are geographically adjacent thereto by using terminal information broadcasted from each terminal, and the paging operation forms a D2D link for a single direction transmission between terminals which want to perform communication. The data traffic communication operation performs link scheduling and corresponding data transmission based on links formed through these operations.
Various applications or user groups may use such D2D communications, and may have different priorities. A related technique for performing communications between devices having different priorities is disclosed in Korean Patent Publication No. 2014-0129503 “SCHEME FOR D2D COMMUNICATION USING PRIORITY.”